1. Update your phone to 7740 2. Update to 8107 3. Insert sim card into an AT&T Android LTE phone 4. Go to att.com and switch plan to Data Pro 4g LTE plan. If the website does not work you may need to call customer support. 5. Setup VVM on the borrowed Android LTE phone (make sure your friend knows the VM password so they can re-add it when they put their sim card back in.) 6.Insert sim card back into Windows Phone 7. Call Voicemail 8. Wait for VVM to show up on phone (mine showed up after calling voicemail). 9. If sync error, edit the APN as follows

Before anyone goes flashing their phone with a 8107 ROM however there is a rumour that when 8107 does eventually come to AT&T Windows Phones, it will bring Visual Voice Mail support with it, and it may be safer to simply wait it out.